364 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
Knowledge of the Insect’s Habits of Flight Necessary 
for Control 
The widespread depredations of the striped cucumber beetle and the 
need of adequate control measures are too well known to require mention 
here. The purely mechanical injury which it causes in its feeding is not 
the only offence laid at its door. The role of the beetle in the trans¬ 
mission of certain cucurbit diseases, as shown by recent investigators, 
proves it of even greater economic importance. The beetle not only 
disseminates cucurbit mosaic, but is also the chief if not the only carrier 
of the bacterial wilt of cucurbits. The damage caused by the beetle 
has been .variously estimated at from $3,000,000 to $5,000,000 a year. 
Many control measures have been suggested and tested, some of which 
have proved effective in killing or repelling the beetles present, but 
none could be recommended as a complete control. The lack of efficiency 
has been due chiefly to the migratory habits of the beetles, for although 
they may be completely destroyed or driven away from a treated area, 
migration from surrounding untreated plantings will soon reestablish 
infestation. This project was undertaken, therefore, to define the limits 
of the powers of flight of the beetle; the maximum and average distance 
covered on the wing, and the frequency with which the beetle migrates 
from one planting to another. 
Experiments in Marking 
Experiments in marking beetles were begun in 1920, considerable 
time being devoted to finding a material and a method which would 
allow rapid and successful marking. The principal difficulty was in 
securing adhesion of the marking colors to the elytra. Among the sub¬ 
stances tested were glue, colored chalks, aniline dyes, India inks, and 
shellac, and although tested singly and in various combinations, all 
proved unsuitable. Glue, dyed with an India ink, dried so slowly that 
beetles marked with it soon became entangled and incapable of flight. 
Colored chalks, which had been used successfully by other workers in 
marking bees and many Diptera, failed to adhere to the almost hairless 
bodies of the beetles. Aniline dyes or India inks, used without an 
adhesive, were almost indiscernable on drying. Commerical shellac 
had the same objectionable qualities as glue. The pigment finally em¬ 
ployed was a precipitate resulting from thoroughly mixing two parts 
shellac and one part of various India inks. This precipitate was very 
adherent to the elytra of the beetle. It retained its color well and dried 
quickly but could not be suitably applied except by means of a small 
